Summary in english:
From the video-tapings carried out fortnightly of a child that has been in contact with the two target languages (Basque and Spanish), we have gone on to analysing the acquisition and development of the cases in Basque and of the corresponding prepositions and pronouns in Spanish, from ages 1;11 to age 3;06. The result show that most of the cases in Basque as well as their corresponding prepositions and pronouns in Spanish, and the functions they fulfil, have appeared in the target child languages before the age of three and a half.